In many audio amplifiers a so-called single-ended configuration is used. In a single-ended configuration only one terminal of the loudspeaker load is connected to the output of the power amplifier. If a symmetrical power supply is available the other loudspeaker terminal is connected to ground. If only a single (asymmetrical) power supply is available a DC-blocking capacitor is needed between the loudspeaker and ground. The average voltage across the DC-blocking capacitor equals half the supply voltage. The amplifier may have a feedback loop between the output and an inverting input of the amplifier.